The determination of the electron-phonon interaction from tunneling data in the two-band superconductor MgB2
نویسنده
چکیده
We calculate the tunneling density of states (DOS) of MgB2 for different tunneling directions, by directly solving the real-axis, two-band Eliashberg equations (EE). Then we show that the numeric inversion of the standard singleband EE, if applied to the DOS of the two-band superconductor MgB2, may lead to wrong estimates of the strength of certain phonon branches (e.g. the E2g) in the extracted electron-phonon spectral function α F (ω). The fine structures produced by the two-band interaction turn out to be clearly observable only for tunneling along the ab planes in high-quality single crystals. The results are compared to recent experimental data.
منابع مشابه
Extraction of the electron-phonon interaction from tunneling data in the multigap superconductor MgB2
O. V. Dolgov, R. S. Gonnelli, G. A. Ummarino, A. A. Golubov, S. V. Shulga, and J. Kortus Max-Planck Institut für Festkörperforschung, Stuttgart, Germany Eberhard-Karls-Universität Tübingen, Tübingen, Germany INFM-Dipartimento di Fisica, Politecnico di Torino, 10129 Torino, Italy University of Twente, Faculty of Science and Technology, 7500 AE Enschede, The Netherlands Institute für Festkörperun...
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